Heretofore, as shown in FIG. 2, as an objective lens to be employed for an optical pickup device suitable for recording or reproducing HD or DVD, an optical pickup has been reported (refer to JP-A-2000-90477. Hereinafter, referred to as Patent Document 1), which employs as an objective lens 62 a complex lens constituted by a reference lens 62a having a converging power made of a synthesized resin or a glass material and a close-contact lens 62b made of a UV-curable resin material in close contact with the reference lens 62a. 
Here, in FIG. 2, 62e indicates a surface of the reference lens 62a on the side of a light source (a surface of an objective lens 62 on the side of the light source), 62f indicates a surface of the reference lens 62a on the side of an optical disk (a surface of the close-contact lens 62b on the side of the light source) and 62g indicates a surface of the close-contact lens 62b on the side of the optical disk.
According to this conventional example, it is reported to be possible to compensate chromatic aberrations for two laser light beams of different wavelengths including a red laser light beam of wavelength of about 650 nm and a blue laser light beam of wavelength of about 430 nm.
According to this conventional example, a compatible performance can be obtained for optical disks of HD having a plurality of protective layers and of DVD having a plurality of protective layers. However, there is no specific description as to the thickness of the protective layers of these optical disks or the numerical aperture of the objective lens, and examples of this conventional example only describes as to a wavefront aberration for blue laser light and a wavefront aberration for red laser light, and it is unclear that correction to the spherical aberration can actually be effected when how much difference is given between the thickness of the protective layers.
Further, there is no description in the Patent Document 1 as to recording or reproducing of an information of CD by employing a red laser light of wavelength of about 780 nm. Therefore, it is considered that the conventional example does not have a compatible performance of recording or reproducing HD, DVD and CD, and there has been a problem that recording or reproducing of CD has not been possible.